Credit Concentration (Details) (USD $)	3 Months Ended
	Mar. 31, 2015 properties		Mar. 31, 2014	Dec. 31, 2014
Concentration by investment:
Number of properties in diversified portfolio	1,316	[1]
Percent of NOI	100.00%	[1],[2]
Net Operating Income	$ 517,716,000	[1]	$ 460,376,000
Credit Concentration (Textual) [Abstract]
Percentage total investments with top five customers				49.00%
Genesis HealthCare [Member]
Concentration by investment:
Number of properties in diversified portfolio	180	[1]
Percent of NOI	17.00%	[1],[2]
Net Operating Income	87,277,000	[1]
Sunrise Senior Living [Member]
Concentration by investment:
Number of properties in diversified portfolio	143	[1],[3]
Percent of NOI	14.00%	[1],[2],[3]
Net Operating Income	71,268,000	[1],[3]
Brookdale [Member]
Concentration by investment:
Number of properties in diversified portfolio	146	[1]
Percent of NOI	8.00%	[1],[2]
Net Operating Income	42,092,000	[1]
Benchmark Senior Living [Member]
Concentration by investment:
Number of properties in diversified portfolio	49	[1]
Percent of NOI	4.00%	[1],[2]
Net Operating Income	21,726,000	[1]
Revera [Member]
Concentration by investment:
Number of properties in diversified portfolio	71	[1],[3]
Percent of NOI	4.00%	[1],[2],[3]
Net Operating Income	19,121,000	[1],[3]
Remaining Portfolio [Member]
Concentration by investment:
Number of properties in diversified portfolio	727	[1]
Percent of NOI	53.00%	[1],[2]
Net Operating Income	$ 276,232,000	[1]

[1] (1)     Genesis Healthcare is in our triple-net segment. Sunrise Senior Living and Revera are in our seniors housing operating segment. Brookdale Senior Living and Benchmark Senior Living are in both our triple-net and seniors housing operating segments.

[2] (2)     NOI with our top five relationships comprised 49% of total NOI for the year ending December 31, 2014

[3] (3)     Revera owns a controlling interest in Sunrise.